PEP and 2-PG have similar amounts of potential metabolic energy with respect to decomposition to P_i, CO₂ and H₂O, but the enolase reaction:

Question

Quizplus · Accepted Answer

The enolase reaction rearranges 2-PG into a form from which more potential energy can be released by hydrolysis. This is because the rearranged form (PEP) has a higher phosphate group transfer potential than 2-PG. Therefore, more energy can be released when PEP is converted to downstream metabolites compared to 2-PG. Option A is incorrect because there is no evidence to suggest that enolase creates a more unstable reactive intermediate compared to other enzymes involved in glycolysis. Option C is incorrect because there is no evidence to suggest that enolase rearranges 2-PG to a form with greater binding potential to the enzyme. Option D is incorrect because enolase does not directly change the ΔG of the reaction, it only rearranges the substrate from 2-PG to PEP. Option E is incorrect because option B is true.

PEP and 2-PG Have Similar Amounts of Potential Metabolic Energy